<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    * {
      margin: 0;
      padding: 0;
    }

    .containner {
      margin: auto;
      margin-top: 20px;
      display: table;
      border-collapse: collapse;
    }

    .row {
      display: table-row;
    }

    .cell {
      display: table-cell;
      width: 100px;
      height: 100px;
      border: 0.5px solid #000;
    }

    .grid {
      margin-top: 20px;
      display: grid;
      grid-template-columns: repeat(6, 100px);
      grid-template-rows: repeat(2, 100px);
      justify-content: center;
    }

    .box {
      border: 0.5px solid #000;
    }
  </style>
</head>

<body>
  <div class="containner">
    <div class="row">
      <div class="cell"></div>
      <div class="cell"></div>
      <div class="cell"></div>
      <div class="cell"></div>
      <div class="cell"></div>
      <div class="cell"></div>
    </div>
    <div class="row">
      <div class="cell"></div>
      <div class="cell"></div>
      <div class="cell"></div>
      <div class="cell"></div>
      <div class="cell"></div>
      <div class="cell"></div>
    </div>
  </div>

  <div class="grid">
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
    <div class="box"></div>
  </div>
</body>

</html>